When Peterson, the Arizona Cardinals' versatile cornerback, trained this offseason, all of that ran through his mind, but his focus had a tendency to shift toward Johnson, the Detroit Lions star who is the first marquee wide receiver on the Cardinals’ 2013 schedule.

“That’s all I’ve been thinking about,” Peterson said. “I just want to go out there. I’ve been preparing well all week. I believe I have a good feeling of what he wants to do.”

That’s as much because of Peterson’s diligent film study as it is for a newfound understanding of how wide receivers think. Because he is one.

Patrick Peterson spent much of his offseason looking ahead to Sunday's visit from Calvin Johnson.

First-year Cardinals coach Bruce Arians installed an offensive package specifically with Peterson lined up at wide receiver that includes more than 60 plays. Peterson has not only digested them but has also started to perfect his receiver skills, in part by picking the brain of teammate and All-Pro wideout Larry Fitzgerald.

Peterson better understands how receivers think -- which routes they’re going to run in certain splits, how they want to attack a defensive back, what they’re looking for in specific coverage.

By getting in the Johnson’s mind, Peterson feels he has an advantage.

Then he has to deal with the physical.

Johnson is 6-foot-5, 236 pounds. Peterson is 6-foot-1, 219.

Peterson is physically gifted, having the tools to present a threat in all three facets of the game. But even he is impressed with Johnson.

“The way he moves in and out of traffic, the way he gets off of press coverage. He’s big but he moves like a little guy,” Peterson said. “He has little-guy speed. He comes in and out of his breaks, which is really impressive for a tall guy that can do that.

“Just watching him on film, nothing seems to amaze me. He’s always doing the unthinkable each and every Sunday, so my job is to slow that down.”

He won’t always be doing it alone.

There will be times when it will be Peterson versus Johnson, and Arians expects his star corner to win some of those battles. But he’ll have help over the top as much as possible.

Peterson clearly stated his game plan for Sunday: He wants to be physical with Johnson. Peterson approached last season's meeting with Detroit the same way, keeping his hands on Johnson whenever permitted. Johnson had 121 yards on 10 catches, but he never made it to the end zone.

“I kept him in front of me,” Peterson said. “That was my whole goal, eliminating those big plays, because that’s when he seems to get on, once you give up that 40-plus yard play.”

Whether Peterson can do it again will set the tone for his reputation this season.

He claimed to have improved his technique during the offseason, working on being more patient on the line of scrimmage while keeping his hands high.

The higher his hands, the better chance he can knock a receiver off a route -- well, receivers who aren’t 6-5, 236.